Geometry

Angle

Definition	Circle	Example
Two rays with a common endpoint.

Sides

Definition	Drawing	Example
A ray that is part of an angle.

Vertex

Definition	Drawing	Example
The common endpoint of two rays that form an angle.

Degree

Definition	Drawing	Example
The most common unit of unit for angles.

Right Angle

Definition	Drawing	Example
An angle that measures exactly 90 degrees. It looks like a perfect L.

Acute Angle

Definition	Drawing	Example
An angle that measures between 0 degrees and 90 degrees. It looks like a skinny L.

Obtuse Angle

Definition	Drawing	Example
An angle that measures between 90 degrees and 180 degrees.

Straight Angle

Definition	Drawing	Example
An angle that measures exaclty 180 degrees. It looks like a straight line.

Congruent Angle

Definition	Drawing	Example
Are angles that are equal. They have the same measure.

Vertical Angle

Definition	Drawing	Example
Angles formed when two lines intersect. They are opposite each other. All vertical angles are congruent.

Complementary Angle

Definition	Drawing	Example
The sum of the angles measurement equals 90 degrees.

Supplementary Angle

Definition	Drawing	Example
The sum of two equals 180 degrees.

Triangle

Definition	Drawing	Example
A polygon with 3 sides. All three angles in a triangle add up to 180 degrees.

Acute Triangle

Definition	Drawing	Example
All interior angles are acute.

Obtuse Triangle

Definition	Drawing	Example
One interior angle is obtuse.

Right Triangle

Definition	Drawing	Example
One interior angle is a right angle.

Scalene Triangle

Definition	Drawing	Example
It has no congruent sides or angles

Isoceles Triangle

Definition	Drawing	Example
Has two congruent sides and congruent angles.

Equilateral Triangle

Definition	Drawing	Example
It has all sides that are congruent and all angles are congruent.

Quadrilateral

Definition	Drawing	Example
Four sided polygon. Interior angles add up to 360 degrees.

Parallelogram

Definition	Drawing	Example
A quadrilateral with both pairs of opposite sides. Parellel = 360 degrees.

Rectangle

Definition	Drawing	Example
Parallelogram with four right angles equaling 360 degrees.

Rhombus

Definition	Drawing	Example
Parallelogram with four congruent sides which equals 360 degrees.

Square

Definition	Drawing	Example
A rhombus with four right angles equaling 360 degrees.

Trapezoid

Definition	Drawing	Example
A quadrilateral with exactly one pair of parallal sides which equals 360 degrees.

Similiar Figures

Definition	Drawing	Example
They are shapes that are the same shape but not the same size. All similiar shapes have corresponding parts. Sizes of the figures that match: If sides of the figure that match the corresponding parts are proportional.

Corresponding Sides

Definition	Drawing	Example
Matching sides in a triangle that are the same.

Congruent Figures

Definition	Drawing	Example
Figures that have the same size and shape.